--- /sys/net/if_gif.c.orig	2008-10-03 14:18:50.000000000 +0400
+++ /sys/net/if_gif.c	2008-10-03 11:43:48.000000000 +0400
@@ -81,6 +81,7 @@
 
 #include <netinet/ip_encap.h>
 #include <net/ethernet.h>
+#include <net/if_vlan_var.h>
 #include <net/if_bridgevar.h>
 #include <net/if_gif.h>
 
@@ -560,6 +561,31 @@
 					m->m_flags |= M_MCAST;
 				ifp->if_imcasts++;
 			}
+			/* Check vlan tagging on received frame. */
+			/* Probably should be moved somewhere up. */
+			if (ntohs(eh->ether_type) == ETHERTYPE_VLAN) {
+				/* Copy from if_ethersubr.c */
+				struct ether_vlan_header *evl;
+				if (m->m_len < sizeof(*evl) &&
+				    (m = m_pullup(m, sizeof(*evl))) == NULL) {
+#ifdef DIAGNOSTIC
+					if_printf(ifp, "cannot pullup VLAN header\n");
+#endif
+					ifp->if_ierrors++;
+					m_freem(m);
+					return;
+				}
+
+				evl = mtod(m, struct ether_vlan_header *);
+				m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag);
+				m->m_flags |= M_VLANTAG;
+
+				bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN,
+				      ETHER_HDR_LEN - ETHER_TYPE_LEN);
+				m_adj(m, ETHER_VLAN_ENCAP_LEN);
+				/* End of copy */
+			}
+			
 			BRIDGE_INPUT(ifp, m);
 
 			if (m != NULL && ifp != oldifp) {